黄河下游河道输沙沿程调整变化模拟

Simulation of Sediment Transport in the Lower Yellow River

黄河下游河道输沙具有“多来多排多淤”的特点,一般采用考虑上站来水含沙量的输沙率经验公式描述。通过比较输沙率经验公式与不平衡输沙理论方程之间的区别与联系,从理论上对经验公式的指数变化规律进行了研究,并构建提出了一种变幂指数的泥沙输移模型。基于所建立的泥沙输移变幂指数模型,结合黄河下游河道沿程实测水沙资料,重点对花园口—高村(游荡型)、艾山—利津(弯曲型)段输沙沿程调整变化情况进行了模拟计算。结果表明,计算值与实测值基本一致,确定系数均大于0.97。

The law of sediment transport in the lower Yellow River is very complex, when the amount of sediment coming from upstream in creases, the result of self adjustment is in the direction of increasing the outgoing sediment load from the reach. This is the so called “the more it comes, the more it goes” which is described by the empirical power formula of Q =KS0aQb. Based on the mathematic analysis on the S relation between the empirical formula and the non equilibrium sediment transport theory equation, a varying power exponent model of sedi ment transport for alluvial rivers was proposed. Based on the actual water and sediment volumes during the period of 1950-2010 in the lower Yellow River, the sediments transport which from Huayuankou to Gaocun and from Aishan to Lijin was simulated by applying the varying power exponent model. The calculation results show that the calculated values of the deposition amount are basically in consistent with the measured values, the correlation coefficients R2 is higer than 0.97.